Billionaire Cashes In
On Offshore Oil Rush

With Supply Scarce,
His Rigs Are Hot;
$600,000 Day Rate

By

Guy Chazan

Updated April 1, 2008 11:59 p.m. ET

(See Corrections & Amplifications item below.)

LONDON -- As a buccaneering oil trader, John Fredriksen shipped crude from trouble spots like Iran and used hardball tactics to build up the world's biggest tanker fleet. The son of a welder, this modern-day Onassis is now Norway's richest man, worth at least $7 billion.